These humanoids have flesh that resembles a peeled orange or other citrus fruit: semi-translucent with prominent veins. Brightly colored, some Rutaceaens are orange, some are yellow, and some green. They prefer warm climates with lots of rainfall.
A slow, stupid creature that crawls onto people and latches onto them, often on feet, hands, and other extremities, numbing down the area and slowly feeding on it. It's easy to avoid while awake, but nearly impossible to remove once attached. Many an adventurer has been forced to hack off an arm or leg after waking with a Stoneleech wrapped around it. Sleep with one eye open! (This idea came from "Wizard's Rule")